scholarly journals Corticogeniculate feedback sharpens the temporal precision and spatial resolution of visual signals in the ferret

2017 ◽  
Vol 114 (30) ◽  
pp. E6222-E6230 ◽  
Author(s):  
J. Michael Hasse ◽  
Farran Briggs

The corticogeniculate (CG) pathway connects the visual cortex with the visual thalamus (LGN) in the feedback direction and enables the cortex to directly influence its own input. Despite numerous investigations, the role of this feedback circuit in visual perception remained elusive. To probe the function of CG feedback in a causal manner, we selectively and reversibly manipulated the activity of CG neurons in anesthetized ferrets in vivo using a combined viral-infection and optogenetics approach to drive expression of channelrhodopsin2 (ChR2) in CG neurons. We observed significant increases in temporal precision and spatial resolution of LGN neuronal responses to drifting grating and white noise stimuli when CG neurons expressing ChR2 were light activated. Enhancing CG feedback reduced visually evoked response latencies, increased spike-timing precision, and reduced classical receptive field size. Increased precision among LGN neurons led to increased spike-timing precision among granular layer V1 neurons as well. Together, our findings suggest that the function of CG feedback is to control the timing and precision of thalamic responses to incoming visual signals.

2015 ◽  
Vol 114 (4) ◽  
pp. 2204-2219 ◽  
Author(s):  
Clifford H. Keller ◽  
Terry T. Takahashi

Spike rate adaptation (SRA) is a continuing change of responsiveness to ongoing stimuli, which is ubiquitous across species and levels of sensory systems. Under SRA, auditory responses to constant stimuli change over time, relaxing toward a long-term rate often over multiple timescales. With more variable stimuli, SRA causes the dependence of spike rate on sound pressure level to shift toward the mean level of recent stimulus history. A model based on subtractive adaptation (Benda J, Hennig RM. J Comput Neurosci 24: 113–136, 2008) shows that changes in spike rate and level dependence are mechanistically linked. Space-specific neurons in the barn owl's midbrain, when recorded under ketamine-diazepam anesthesia, showed these classical characteristics of SRA, while at the same time exhibiting changes in spike timing precision. Abrupt level increases of sinusoidally amplitude-modulated (SAM) noise initially led to spiking at higher rates with lower temporal precision. Spike rate and precision relaxed toward their long-term values with a time course similar to SRA, results that were also replicated by the subtractive model. Stimuli whose amplitude modulations (AMs) were not synchronous across carrier frequency evoked spikes in response to stimulus envelopes of a particular shape, characterized by the spectrotemporal receptive field (STRF). Again, abrupt stimulus level changes initially disrupted the temporal precision of spiking, which then relaxed along with SRA. We suggest that shifts in latency associated with stimulus level changes may differ between carrier frequency bands and underlie decreased spike precision. Thus SRA is manifest not simply as a change in spike rate but also as a change in the temporal precision of spiking.


2015 ◽  
Vol 16 (S1) ◽  
Author(s):  
Jan-Hendrik Schleimer ◽  
Janina Hesse ◽  
Susanne Schreiber

2005 ◽  
Vol 17 (7) ◽  
pp. 1577-1601 ◽  
Author(s):  
Michael Stiber

The effects of spike timing precision and dynamical behavior on error correction in spiking neurons were investigated. Stationary discharges—phase locked, quasiperiodic, or chaotic—were induced in a simulated neuron by presenting pacemaker presynaptic spike trains across a model of a prototypical inhibitory synapse. Reduced timing precision was modeled by jittering presynaptic spike times. Aftereffects of errors—in this communication, missed presynaptic spikes—were determined by comparing postsynaptic spike times between simulations identical except for the presence or absence of errors. Results show that the effects of an error vary greatly depending on the ongoing dynamical behavior. In the case of phase lockings, a high degree of presynaptic spike timing precision can provide significantly faster error recovery. For nonlocked behaviors, isolated missed spikes can have little or no discernible aftereffects (or even serve to paradoxically reduce uncertainty in postsynaptic spike timing), regardless of presynaptic imprecision. This suggests two possible categories of error correction: high-precision locking with rapid recovery and low-precision nonlocked with error immunity.


PLoS ONE ◽  
2012 ◽  
Vol 7 (4) ◽  
pp. e35320 ◽  
Author(s):  
Steven J. Ryan ◽  
David E. Ehrlich ◽  
Aaron M. Jasnow ◽  
Shabrine Daftary ◽  
Teresa E. Madsen ◽  
...  

2006 ◽  
Vol 15 (10) ◽  
pp. 2450-2457 ◽  
Author(s):  
Zhang Su-Hua ◽  
Zhan Yong ◽  
Yu Hui ◽  
An Hai-Long ◽  
Zhao Tong-Jun

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